AASHTO T 104-99 (2020) PDF Download

AASHTO T 104-99 (2020) is a standard method of testing the soundness of aggregates using either sodium sulfate or magnesium sulfate. The purpose of this test is to determine the resistance of the aggregates to disintegration when immersed in saturated solutions of these salts.

The test involves the immersion of the aggregates in the saturated solution, followed by oven drying to remove the moisture and dehydrate the salt precipitated in the pore spaces. The internal expansive force, resulting from the rehydration of the salt during re-immersion, mimics the expansion of water during freezing, which is a common weathering action.

The test is particularly useful for assessing the durability and potential weathering effects on aggregates when there is limited information available from service records. It should be noted that the results obtained using sodium sulfate and magnesium sulfate may differ significantly, and therefore, careful consideration must be given when specifying the requirements for these test methods in any specifications.